Molded product manufactured from high heat resistant polycarbonate ester

ABSTRACT

The present invention relates to a molded product manufactured from a high heat resistant bio-based polycarbonate ester. More specifically, the molded product has excellent heat resistance, and thus can be applied to various fields such as those of automobiles, electrical electronics, displays, aviation, machines, lighting, medicine or food.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/KR2018/013491 filed Nov. 8, 2018, claiming priority based on KoreanPatent Application No. 10-2017-0148867 filed Nov. 9, 2017 and Koreanpatent Application No. 10-2018-0135681 filed Nov. 7, 2018.

TECHNICAL FIELD

The present invention relates to an article molded from a bio-basedpolycarbonate ester having high heat resistance. More specifically, themolded article is excellent in heat resistance, so that it can beapplied to various fields such as automobiles, electric/electronic,display, aviation, machine, lighting, medical, and food.

BACKGROUND ART OF THE INVENTION

A bio-based polycarbonate ester prepared by melt polycondensation of1,4:3,6-dianhydrohexitol with a carbonate or1,4-cyclohexanedicarboxylate is a bioplastic that contains a bio-basedmonomer derived from a bio-source, that is 1,4:3,6-dianhydrohexitol. Thebio-based polycarbonate ester has high transparency of PMMA (poly(methylmethacrylate)) and high heat resistance of bisphenol A (BPA)polycarbonate.

The structural features of such bio-based polycarbonate esters lie inthat they do not contain BPA that causes environmental hormones and thatit is also possible to improve the ductility of the molecular structureof 1,4:3,6-dianhydrohexitol by copolymerizing a1,4-cyclohexanedicarboxylate monomer having an aliphatic ring molecularstructure. In addition, it is possible to compensate the disadvantage ofa carbonate bond by replacing some of the carbonate bonds with an esterbond.

Meanwhile, 1,4-dimethyl-cyclohexanedicarboxylate (DMCD) or1,4-cyclohexanedicarboxylic acid (CHDA), which is a hydrolysis productof DMCD, has a cyclohexane ring structure in its molecule center. Thus,in the case where it is incorporated into a polymer chain, it ispossible to improve not only the UV stability and weatherability of thepolymer, but also such properties of the polymer as gloss retention,yellowing resistance, hydrolytic stability, corrosion resistance, andchemical resistance owing to the unique combination of flexibility andhardness in the molecular structure. If such an aliphatic ring structureas DMCD or CHDA is present in a polymer chain, secondary mechanicalrelaxation of the polymer due to the molecular flip motion of thealiphatic ring would take place to thereby improve the mechanicalproperties of the polymer, particularly to enhance the impact strengththereof.

Meanwhile, highly heat-resistant materials that have a glass transitiontemperature (Tg) of 170° C. or higher and can be applied to such variousfields as automobiles, electronic devices, industrial lighting, andmedical uses have been developed in recent years with an increaseddemand therefore. On the other hand, a bio-based polycarbonate esterprepared by melt polycondensation of 1,4:3,6-dianhydrohexitol with acarbonate or 1,4-cyclohexanedicarboxylate has a Tg of 170° C. or lower,which requires an enhancement in the heat resistance thereof for use asa highly heat-resistant material.

For the purpose of enhancing the heat resistance of BPA polycarbonates,copolymerized polycarbonates have been developed using various monomerswith bulky and rigid structures. However, the monomers having a bulkyand rigid structure are expensive because it is difficult andcomplicated to synthesize them. In addition, it is necessary tosubstitute a large amount of BPA to sufficiently enhance the heatresistance, which gives rise to a problem of impairing the excellentmechanical characteristics as well as transparency and fluidity of theBPA polycarbonates.

DISCLOSURE OF THE INVENTION Technical Problem to be Solved

Accordingly, an object of the present invention is to provide an articlemolded from a highly heat-resistant, bio-based polycarbonate ester thatis prepared from an inexpensive material that meets the enhancement ofheat resistance and economical efficiency and is capable of maintaininghigh transparency of a bio-based polycarbonate ester, whilematerializing high fluidity.

Solution to the Problem

In order to achieve the above object, the present invention provides anarticle molded from a bio-based polycarbonate ester having high heatresistance, wherein the highly heat-resistant, bio-based polycarbonateester comprises a repeat unit 1 represented by the following Formula 1;a repeat unit 2 represented by the following Formula 2; and a repeatunit 3 represented by the following Formula 3:

Advantageous Effects of the Invention

The article of the present invention, which is molded from a highlyheat-resistant, bio-based polycarbonate ester, is eco-friendly becauseit does not contain bisphenols and can be used in various productsbecause it has excellent heat resistance as represented by a glasstransition temperature of 160° C. or higher.

DETAILED DESCRIPTION FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

Molded Article

The present invention provides an article molded from a bio-basedpolycarbonate ester having high heat resistance, wherein the highlyheat-resistant, bio-based polycarbonate ester comprises a repeat unit 1represented by the following Formula 1; a repeat unit 2 represented bythe following Formula 2; and a repeat unit 3 represented by thefollowing Formula 3:

The repeat unit 1 may be obtained from the reaction of1,4:3,6-dianhydrohexitol and a carbonate, the repeat unit 2 may beobtained from the reaction of 1,4:3,6-dianhydrohexitol and1,4-cyclohexanedicarboxylate, and the repeat unit 3 may be obtained fromthe reaction of 1,4:3,6-dianhydrohexitol and a terephthalate.

The cis/trans ratio of 1,4-cyclohexanedicarboxylate in the repeat unit 2may be 1/99 to 99/1%, 20/80 to 80/20%, or 30/70 to 70/30%.

1,4:3,6-dianhydrohexitol may be isomannide, isosorbide, or isoidide.Specifically, it may be isosorbide.

Specifically, the highly heat-resistant, bio-based polycarbonate esteris composed of the repeat units 1 to 3. When the molar fractions of therepeat units 1 to 3 are x, y, and z, respectively, x is a real number ofgreater than 0 to less than 1, y is a real number of greater than 0 to0.7, z is a real number of greater than 0 to 0.6, and x+y+z may be 1.More specifically, x is a real number of greater than 0 to 0.9 orgreater than 0 to 0.8, y is a real number of greater than 0 to 0.6 orgreater than 0 to 0.5, z is a real number of greater than 0 to 0.5 orgreater than 0 to 0.4, and x+y+z may be 1.

The highly heat-resistant, bio-based polycarbonate ester may have aglass transition temperature (Tg) of 160 to 240° C. and a melt flowindex (MI) of 5 to 150 g/10 min when measured at 260° C. under a load of2.16 kg. Specifically, the highly heat-resistant, bio-basedpolycarbonate ester may have a Tg of 170 to 220° C. or 180 to 200° C.and a melt flow index (MI) of 10 to 100 g/10 min or 15 to 50 g/10 minwhen measured at 260° C. under a load of 2.16 kg.

The highly heat-resistant, bio-based polycarbonate ester may have anintrinsic viscosity (IV) of 0.3 to 2.3 dL/g.

In general, a polycarbonate is excellent in heat resistance andmechanical properties, but it is relatively poor in chemical resistance,residual stress, and molding cycle time, as compared with a polyester.As described above, however, a polycarbonate ester containing carbonateand ester bonds together in the single polymer chain thereof would havethe advantages of a polycarbonate and a polyester while thedisadvantages thereof are compensated. Thus, an article molded from thebio-based polycarbonate ester having high heat resistance can be used asa material for various fields that require excellent heat resistance.

The molding process of the highly heat-resistant, bio-basedpolycarbonate ester is not particularly limited. For example, injectionmolding, extrusion molding, blow molding, extrusion blow molding,inflation molding, calender molding, foam molding, balloon molding,vacuum molding, and radiation molding may be adopted.

The use of the article molded from the highly heat-resistant, bio-basedpolycarbonate ester is not particularly limited. But it may be used as asubstitute for conventional heat resistant and optical articles byvirtue of its excellent heat resistance and transparency. Specifically,the molded article may be an automobile part, an electric/electronicpart, a display part, an aviation part, a machine part, a lighting part,a medical product, and a food container.

Process for Preparing a Highly Heat-Resistant, Bio-Based PolycarbonateEster

The highly heat-resistant, bio-based polycarbonate ester of the presentinvention may be prepared by a process as described below.

The process for preparing a highly heat-resistant, bio-basedpolycarbonate ester comprises: (1) converting a compound represented bythe following Formula 4 to an intermediate reactant having a halogenfunctional group at the terminal thereof, followed by a nucleophilicreaction with phenol or a phenol substituent, or subjecting a compoundrepresented by the following Formula 4 to a transesterification oresterification reaction with phenol or a phenol substituent, to preparea compound represented by the following Formula 5; and

(2) subjecting compounds represented by the following Formulae 5 to 7and 1,4:3,6-dianhydrohexitol to a melt polycondensation reaction toprepare a compound containing repeat units 1 to 3 represented by thefollowing Formulae 1 to 3:

In the above Formulae,

R¹ is methyl or hydrogen, and

R² and R³ are each an alkyl group having 1 to 18 carbon atoms or an arylgroup having 6 to 18 carbon atoms, wherein the aryl group may have atleast one substituent selected from the group consisting of an alkylgroup having 1 to 18 carbon atoms, a cycloalkyl group having 4 to 20carbon atoms, an aryl group having 6 to 18 carbon atoms, an alkoxy grouphaving 1 to 18 carbon atoms, a cycloalkoxy group having 4 to 20 carbonatoms, an aryloxy group having 6 to 18 carbon atoms, an alkylsulfonylgroup having 1 to 18 carbon atoms, a cycloalkylsulfonyl group having 4to 20 carbon atoms, an arylsulfonyl group having 6 to 18 carbon atoms,and an ester substituent. Here, the ester substituent may be an alkylester having 1 to 18 carbon atoms, a cycloalkyl ester having 4 to 20carbon atoms, or an aryl ester having 6 to 18 carbon atoms.

Step (1)

In this step, a compound represented by the above Formula 4 is convertedto an intermediate reactant having a halogen functional group at theterminal thereof, followed by a nucleophilic reaction with phenol or aphenol substituent, or a compound represented by the above Formula 4 issubjected to a transesterification or esterification reaction withphenol or a phenol substituent, to prepare a compound represented by theabove Formula 5.

The phenol substituent may be a compound represented by the followingFormula 9.

In the above Formula 9,

R⁵ is an alkyl group having 1 to 18 carbon atoms, a cycloalkyl grouphaving 4 to 20 carbon atoms, an aryl group having 6 to 18 carbon atoms,an alkoxy group having 1 to 18 carbon atoms, a cycloalkoxy group having4 to 20 carbon atoms, an aryloxy group having 6 to 18 carbon atoms, analkylsulfonyl group having 1 to 18 carbon atoms, a cycloalkylsulfonylgroup having 4 to 20 carbon atoms, an arylsulfonyl group having 6 to 18carbon atoms, or an ester substituent. Here, the ester substituent maybe an alkyl ester having 1 to 18 carbon atoms, a cycloalkyl ester having4 to 20 carbon atoms, or an aryl ester having 6 to 18 carbon atoms.

Intermediate Reactant

The intermediate reactant having a halogen functional group at theterminal thereof may be a compound represented by the following Formula8.

In the above Formula 8,

R⁴ is each independently F, Cl, or Br.

Specifically, the intermediate reactant having a halogen functionalgroup at the terminal thereof may be terephthaloyl chloride (TPC) inwhich R⁴ is Cl.

In addition, the intermediate reactant having a halogen functional groupat the terminal thereof may be prepared by reacting the compoundrepresented by the above Formula 4 (a dicarboxylate or a dicarboxylicacid) with a halogenated compound.

The halogenated compound may be at least one selected from the groupconsisting of phosgene, triphosgene, thionyl chloride, oxalyl chloride,phosphorus trichloride, phosphorus pentachloride, phosphoruspentabromide, and cyanuric fluoride. Specifically, the halogenatedcompound may be at least one chlorinating agent selected from the groupconsisting of phosgene, thionyl chloride, and oxalyl chloride, fromwhich reaction by-products can be readily removed. In addition, thehalogenated compound may be preferably phosgene from a commercialviewpoint.

The amount of the halogenated compound to be added may be 1 to 10 times,1.5 to 7.5 times, or 2 to 5 times the molar amount of the compound ofthe above Formula 4 initially employed.

The reaction conditions and time in the conversion to the intermediatereactant may vary depending on the type of the compound of the aboveFormula 4 and the halogenated compound. Specifically, the conversion tothe intermediate reactant may be carried out under atmospheric pressureat a temperature of −30 to 150° C. for 5 minutes to 48 hours. Morespecifically, the conversion to the intermediate reactant may be carriedout under atmospheric pressure at a temperature of 20 to 100° C. or 40to 80° C. for 10 minutes to 24 hours.

In the conversion to the intermediate reactant, an organic solvent maybe used to dissolve or disperse the compound of the above Formula 4. Insuch event, the organic solvent that may be used may be, for example,benzene, toluene, xylene, mesitylene, methylene chloride,dichloroethane, chloroform, carbon tetrachloride, monochlorobenzene,o-dichlorobenzene, tetrahydrofuran, dioxane, acetonitrile, or the like.

In order to increase the conversion rate and the reaction yield of theintermediate reactant, a catalyst may be used depending on the kind ofthe compound of the above Formula 4 and the halogenated compound used inthe conversion to the intermediate reactant. The type of the catalyst isnot particularly limited as long as it meets this object. Here, anorganic catalyst that may be used includes dimethylformamide,dimethylacetamide, methylpyrrolidone, dimethyl imidazolidinone,tetramethylurea, tetraethylurea, and tetrabutylurea. An inorganiccatalyst may include aluminum chloride (AlCl₃), iron chloride (FeCl₃),bismuth chloride (BiCl₃), gallium chloride (GaCl₃), antimonypentachloride (SbCl₅), boron trifluoride (BF₃), bismuthtrifluoromethanesulfonate (Bi(OTf)₃), titanium tetrachloride (TiCl₄),zirconium tetrachloride (ZrCl₄), titanium tetrabromide (TiBr₄), andzirconium tetrabromide (ZrBr₄). Among these, dimethylformamide,tetramethylurea, or dimethyl imidazolidinone may be used as the organiccatalyst, and aluminum chloride or titanium tetrachloride may be used asthe inorganic catalyst. In addition, dimethylformamide may be used asthe commercially preferable organic catalyst, and aluminum chloride maybe used as the commercially preferable inorganic catalyst.

The amount of the catalyst to be used in the conversion to theintermediate reactant is not particularly limited, but varies dependingon the kind of the compound of the above Formula 4 and the halogenatedcompound. Specifically, the amount of the catalyst used in theconversion to the intermediate reactant may be in the range of greaterthan 0 to 10% by mole, greater than 0 to 5% by mole, or greater than 0to 3% by mole, based on the total molar amount of the compound of theabove Formula 4 initially employed. If the amount of the catalyst usedin the conversion to the intermediate reactant is within the aboverange, it is possible to prevent the problems that the reaction rate isreduced and that a runaway reaction and an exothermic reaction areinduced.

In the above step (1), terephthalic acid (TPA) in the case where R¹ ishydrogen in the above Formula 4 or dimethyl terephthalate (DMT) in thecase where R¹ is methyl in the above Formula 4 is converted to TPC as anintermediate reactant having a halogen functional group at the terminalthereof, followed by a reaction with phenol or a phenol substituent, toprepare diphenyl terephthalate (DPT) represented by the above Formula 5(see Reaction Scheme 1 below, wherein Me is methyl, and Ph is a phenylgroup).

The molar ratio of the compound represented by the above Formula 8 tophenol or the phenol substituent in the above nucleophilic reaction maybe 1:1 to 5. Specifically, the molar ratio of the compound representedby the above Formula 8 to phenol or the phenol substituent in the abovenucleophilic reaction may be 1:2 to 3. If the molar ratio of thecompound represented by the above Formula 8 to phenol or the phenolsubstituent in the above nucleophilic reaction is within the aboverange, it is possible to prevent the problem that the final yield of thecompound (DPT) represented by the above Formula 5 is reduced, which maybe caused by the use of an excessive amount of phenol or the phenolsubstituent.

Transesterification or Esterification Reaction

In addition, in the above step (1), TPA in the case where R¹ is hydrogenin the above Formula 4 or DMT in the case where R¹ is methyl in theabove Formula 4 is subjected to a transesterification or esterificationreaction with phenol or a phenol substituent to prepare a compoundrepresented by the above Formula 5 (see Reaction Scheme 1 above).

The transesterification or esterification reaction may be carried out at20 to 300° C. Specifically, the transesterification or esterificationreaction may be carried out under atmospheric pressure at 50 to 250° C.or 100 to 200° C. or under a pressure of 0.1 to 10 kgf/cm² or 1 to 5kgf/cm² at 50 to 300° C.

The transesterification or esterification reaction may be carried outfor 5 minutes to 48 hours or 10 minutes to 24 hours.

In the transesterification or esterification reaction, the molar ratioof the compound represented by the above Formula 4 to phenol or thephenol substituent may be 1:2 to 40. Specifically, in thetransesterification or esterification reaction, the molar ratio of thecompound represented by the above Formula 4 to phenol or the phenolsubstituent may be 1:3 to 30 or 1:4 to 20. If the molar ratio of thecompound represented by the above Formula 4 to phenol or the phenolsubstituent is within the above range, it is possible to prevent theproblem that the final yield of the compound represented by the aboveFormula 5 is reduced, which may be caused by the use of a small amountof phenol or the phenol substituent.

Step (2)

In this step, the compounds represented by the following Formulae 5 to 7and 1,4:3,6-dianhydrohexitol is subjected to a melt polycondensationreaction to prepare a compound containing repeat units 1 to 3represented by the following Formulae 1 to 3.

In the above Formulae,

R² and R³ are each an alkyl group having 1 to 18 carbon atoms or an arylgroup having 6 to 18 carbon atoms, wherein the aryl group may have atleast one substituent selected from the group consisting of an alkylgroup having 1 to 18 carbon atoms, a cycloalkyl group having 4 to 20carbon atoms, an aryl group having 6 to 18 carbon atoms, an alkoxy grouphaving 1 to 18 carbon atoms, a cycloalkoxy group having 4 to 20 carbonatoms, an aryloxy group having 6 to 18 carbon atoms, an alkylsulfonylgroup having 1 to 18 carbon atoms, a cycloalkylsulfonyl group having 4to 20 carbon atoms, an arylsulfonyl group having 6 to 18 carbon atoms,and an ester substituent. Here, the ester substituent may be an alkylester having 1 to 18 carbon atoms, a cycloalkyl ester having 4 to 20carbon atoms, or an aryl ester having 6 to 18 carbon atoms.

The cis/trans ratio of the compound represented by the above Formula 6may be 1/99 to 99/1%, 10/90 to 90/10%, or 20/80 to 80/20%. In addition,the cis/trans ratio of 1,4-cyclohexanedicarboxylate in the repeat unit 2represented by the above Formula 2 may be 1/99 to 99/1%, 20/80 to80/20%, or 30/70 to 70/30%.

The compound represented by the above Formula 7 may be dimethylcarbonate, diethyl carbonate, di-t-butyl carbonate, diphenyl carbonate,ditolyl carbonate, or bis(methyl salicyl) carbonate.

Specifically, since the above melt polycondensation reaction is carriedout under reduced pressures, diphenyl carbonate or substituted diphenylcarbonate may be used as the compound represented by the above Formula7. The substituted diphenyl carbonate may be ditolyl carbonate orbis(methyl salicyl) carbonate.

1,4:3,6-dianhydrohexitol

1,4:3,6-dianhydrohexitol may be isomannide, isosorbide, or isoidide.Specifically, it may be isosorbide.

Meanwhile, it is very important to maintain a high purity of1,4:3,6-dianhydrohexitol used in the melt polycondensation in order toenhance the heat resistance, transparency, and mechanical properties ofthe highly heat-resistance, bio-based polycarbonate ester thus prepared.1,4:3,6-dianhydrohexitol may be used in the form of powder, flake, or anaqueous solution. If 1,4:3,6-dianhydrohexitol is exposed to air for along period of time, however, it may be readily oxidized and discolored,which may give rise to a problem that the color and molecular weight ofthe final polymer would not be satisfactory. Thus, it is necessary tominimize the exposure of 1,4:3,6-dianhydrohexitol to air. Once1,4:3,6-dianhydrohexitol is exposed to air, it is preferably stored witha deoxidizing agent such as an oxygen absorber. In addition, it is veryimportant to purify 1,4:3,6-dianhydrohexitol by removing the impuritiescontained therein, which have been produced in the multi-step process ofpreparing 1,4:3,6-dianhydrohexitol, in order to maintain the puritythereof. Specifically, in the purification of 1,4:3,6-dianhydrohexitolby distillation, it is crucial to remove a trace level of acidic liquidcomponents that can be removed by an initial separation and alkali metalcomponents that can be removed by a residue separation. Each of theacidic liquid components and alkali metal components may be kept at alevel of 10 ppm or lower, 5 ppm or lower, or 3 ppm or lower.

Highly Heat-Resistance, Bio-Based Polycarbonate Ester

The highly heat-resistance, bio-based polycarbonate ester may becomposed of the above repeat units 1 to 3. Specifically,1,4:3,6-dianhydrohexitol and the compound represented by the aboveFormula 7 may react to form a carbonate bond (repeat unit 1, Formula 1),1,4:3,6-dianhydroxyhexitol and the compound represented by the aboveFormula 6 may react to form an ester bond (repeat unit 2, Formula 2),and 1,4:3,6-dianhydrohexitol and the compound represented by the aboveFormula 5 may react to form an ester bond (repeat unit 3, Formula 3).

In such event, when the molar fraction of 1,4:3,6-dianhydrohexitol is 1,the molar fraction of the compound represented by the above Formula 7 isx, the molar fraction of the compound represented by the above Formula 6(1,4-diphenyl-cyclohexanedicarboxylate, DPCD) is y, and the molarfraction of the compound represented by the above Formula 5 (DPT) is z,x+y+z=1 (see the following Reaction Scheme 2, wherein Ph is phenyl).

Specifically, when the amount of the compounds represented by the aboveFormulae 5 and 6 is 0, a polycarbonate prepared by the meltpolycondensation of 1,4:3,6-dianhydrohexitol and diphenyl carbonate(Formula 7) has a Tg of 163° C. Here, if the amount of the compoundsrepresented by the above Formulae 5 and 6 increases, an ester bond inthe polymer chain increases. When the amount of the compound representedby the above Formula 5 is 1, a polyester having a Tg of 215° C. isproduced. When the amount of the compound represented by the aboveFormula 132 is 1, a polyester having a Tg of 132° C. is produced.

Hence, the content of the repeat units 2 and 3 represented by the aboveFormulae 2 and 3 and the number of carbonate and ester bonds containedin the polymer chain depend on the amount of the compounds representedby the above Formulae 5 and 6. In the case where the polymer chaincontains carbonate and ester bonds together (inclusive of the repeatunits 1 to 3), it is possible to materialize properties suitable forvarious applications. In particular, a polymer that is excellent in heatresistance, transparency, and processability as targeted in the presentinvention can be provided.

The total amount of the compound represented by the above Formula 5, thecompound represented by the above Formula 6, and the compoundrepresented by the above Formula 7 may be 0.7 to 1.3% by mole, 0.9 to1.1% by mole, or 0.95 to 1.05% by mole, respectively, based on 1% bymole of 1,4:3,6-dianhydrohexitol.

In general, a polycarbonate is excellent in heat resistance andmechanical properties, but it is relatively poor in chemical resistance,residual stress, and molding cycle time, as compared with a polyester.As described above, however, a polycarbonate ester containing carbonateand ester bonds together in the single polymer chain thereof would havethe advantages of a polycarbonate and a polyester while thedisadvantages thereof are compensated.

Melt Polycondensation Reaction

The melt polycondensation reaction may be carried out with temperatureelevation and depressurization in a stepwise manner in order to rapidlyremove by-products from the molten reactants having a high viscosity andto promote the polymerization reaction.

Specifically, the melt polycondensation reaction may comprise:

(2-1) a first reaction step under a reduced pressure of 50 to 700 torrat a temperature of 130 to 250° C., 140 to 240° C., or 150 to 230° C.,for 0.1 to 10 hours or 0.5 to 5 hours; and

(2-2) a second reaction step under a reduced pressure of 0.1 to 20 torrat a temperature of 200 to 350° C., 220 to 280° C., or 230 to 270° C.,for 0.1 to 10 hours or 0.5 to 5 hours.

Specifically, the melt polycondensation reaction may comprise:

(2-1) a first reaction step with temperature elevation to 130 to 200°C., followed by depressurization to 200 to 700 torr, and temperatureelevation to 200 to 250° C. at a rate of 0.1 to 10° C./min, followed bydepressurization to 50 to 180 torr; and

(2-2) a second reaction step with depressurization to 1 to 20 torr,followed by temperature elevation to 200 to 350° C. at a rate of 0.1 to5° C./min, and depressurization to 0.1 to 1 torr.

Meanwhile, phenol may be produced as a reaction by-product during themelt polycondensation reaction. It is preferable that phenol produced asa by-product is removed from the reaction system in order to shift thereaction equilibrium towards the production of the polycarbonate ester.If the rate of temperature elevation in the melt polycondensationreaction is within the above ranges, it is possible to prevent theproblem that phenol, a reaction by-product, evaporates or sublimestogether with the reaction raw materials. Specifically, thepolycarbonate ester may be prepared in a batch or continuous process.

In particular, in order to produce a polymer of high transparency,relatively low reaction temperatures are suitable for the meltpolycondensation reaction that uses 1,4:3,6-dianhydrohexitol. Inaddition, in order to secure the mechanical properties of the polymerthus prepared, it is preferable that the melt polycondensation reactionis carried out to a high degree of polymerization. For this purpose, itis effective to use a high viscosity polymerization reactor for the meltpolycondensation reaction. The target viscosity in the meltpolycondensation reaction may be 10,000 to 1,000,000 poises, 20,000 to500,000 poises, or 50,000 to 200,000 poises.

Additional Diol Compound

The reactants (i.e., the compounds represented by the above Formulae 5to 7 and 1,4:3,6-dianhydrohexitol) in the above step (2) may comprise anadditional diol compound other than 1,4:3,6-dianhydrohexitol, theadditional diol compound being not particularly limited. The additionaldiol compound may be a primary, secondary, or tertiary diol compounddepending on the target properties of the polymer.

When the molar amount of the additional diol compound employed is q, themolar amount of 1,4:3,6-dianhydrohexitol employed is to be 1-q. Inparticular, if the additional diol compound is a petrochemical-baseddiol compound, it may be used such that the bio-based carbon content(ASTM-D6866) in the final polymer derived from 1,4:3,6-dianhydrohexitolis at least 1% by mole. In such event, q may satisfy 0≤q≤0.99. That is,the additional diol compound may be used in an amount of less than 99%by mole based on 100% by mole of 1,4:3,6-dianhydrohexitol.

Here, the additional diol compound may be a diol compound having asingle aliphatic ring or a condensed heterogeneous ring at the center ofthe molecule in order to enhance the heat resistance, transparency, UVstability, and weatherability of the highly heat-resistance, bio-basedpolycarbonate ester thus prepared. Meanwhile, when the hydroxyl groupsare in a symmetrical structure, the ring size and heat resistanceproportionally increase. On the other hand, the optical characteristicsdo not depend on the ring size and the positions of the hydroxyl groups,but they vary with the characteristics of each raw material. As the ringsize is bigger, it is more difficult to commercially produce and utilizethe diol compound. Specifically, the additional diol compound may be atleast one selected from the group consisting of1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol,1,4-cyclohexanedimethanol, tricyclodecane dimethanol,3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5,5]undecane,2,2-bis(4-hydroxycyclohexyl)propane, pentacyclopentadecanedimethanol,decalindimethanol, tricyclotetradecanedimethanol, norbornanedimethanol,adamantanedimethanol, bicycle[2.2.2]octane-2,3-dimethanol,1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol,2-methyl-1,4-cyclohexanediol, tricyclodecanediol,pentacyclopentadecanediol, decalindiol, tricyclotetradecanediol,norbornanediol, adamantanediol, and2,2,4,4-tetramethyl-1,3-cyclobutanediol, andtetrahydrofuran-2,5-dimethanol,5,5′-(1-methylethylidene)bis(2-furanmethanol, and2,4:3,5-di-o-methylene-D-mannitol derivable from a bio-based material.Specifically, the additional diol compound may be1,4-cyclohexanedimethanol, 2,2-bis(4-hydroxycyclohexyl)propane,2,2,4,4-tetramethyl-1,3-cyclobutanediol, ortetrahydrofuran-2,5-dimethanol.

Additional Diphenyl Ester Compound

Meanwhile, the reactants (i.e., the compounds represented by the aboveFormulae 5 to 7 and 1,4:3,6-dianhydrohexitol) in the step (2) maycomprise an additional diphenyl ester compound other than the compoundsrepresented by the above Formulae 5 and 6, which are monomers for esterbonds in the polymer chain, depending on the target properties of thepolymer. When the molar amount of the additional diphenyl ester compoundemployed is p, the molar amount of the compounds represented by theabove Formulae 5 to 6 employed is to be 1-p. In such event, p maysatisfy 0≤p<1.

The additional diphenyl ester compound may be one kind or a mixture oftwo or more kinds.

The additional diphenyl ester may be prepared by reacting a primary,secondary, or tertiary dicarboxylate or dicarboxylic acid (hereinafterreferred to as an additional dicarboxylate or dicarboxylic acid) withphenol or a phenol substituent. The additional diphenyl ester may beprepared by reacting an additional dicarboxylate or dicarboxylic acidhaving a single aliphatic ring or a condensed heterogeneous ring at thecenter of the molecule with phenol or a phenol substituent in order toenhance the heat resistance, transparency, UV stability, andweatherability of the highly heat-resistance, bio-based polycarbonateester thus prepared.

The additional dicarboxylate compound may be at least one selected fromthe group consisting of dimethyl tetrahydrofurane-2,5-dicarboxylate,1,2-dimethyl-cyclohexanedicarboxylate,1,3-dimethyl-cyclohexanedicarboxylate, dimethyldecahydro-2,4-naphthalene dicarboxylate, dimethyldecahydro-2,5-naphthalene dicarboxylate, dimethyldecahydro-2,6-naphthalene dicarboxylate, and dimethyldecahydro-2,7-naphthalene dicarboxylate.

The additional dicarboxylic acid compound may be at least one selectedfrom the group consisting of tetrahydrofuran-2,5-dicarboxylic acid,1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid,decahydro-2,4-naphthalenedicarboxylic acid,decahydro-2,5-naphthalenedicarboxylic acid,decahydro-2,6-naphthalenedicarboxylic acid, anddecahydro-2,7-naphthalenedicarboxylic acid.

Specifically, the additional diphenyl ester may be prepared fromdimethyl tetrahydrofurane-2,5-dicarboxylate ortetrahydrofuran-2,5-dicarboxylic acid, or dimethyldecahydro-2,6-naphthalene dicarboxylate ordecahydro-2,6-naphthalenedicarboxylic acid, derivable from a bio-basedmaterial.

Catalyst for the Melt Polycondensation Reaction

In the above melt polycondensation reaction, a catalyst may be used forenhancing the reactivity of the reaction. The catalyst may be added tothe reaction step at any time, but it is preferably added before thereaction.

Any alkali metal and/or alkali earth metal catalyst commonly used in apolycarbonate melt polycondensation reaction may be used as thecatalyst. The catalyst may be used in combination with a basic ammoniumor amine, a basic phosphorous, or a basic boron compound. Alternatively,it may be used alone. Examples of the alkali metal catalysts may includelithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide(KOH), cesium hydroxide (CsOH), lithium carbonate (Li₂CO₃), sodiumcarbonate (Na₂CO₃), potassium carbonate (K₂CO₃), cesium carbonate(Cs₂CO₃), lithium acetate (LiOAc), sodium acetate (NaOAc), potassiumacetate (KOAc), cesium acetate (CsOAc), and the like. In addition,examples of the alkali earth metal catalysts may include calciumhydroxide (Ca(OH)₂), barium hydroxide (Ba(OH)₂), magnesium hydroxide(Mg(OH)₂), strontium hydroxide (Sr(OH)₂), calcium carbonate (CaCO₃),barium carbonate (BaCO₃), magnesium carbonate (MgCO₃), strontiumcarbonate (SrCO₃), calcium acetate (Ca(OAc)₂), barium acetate(Ba(OAc)₂), magnesium acetate (Mg(OAc)₂), strontium acetate (Sr(OAc)₂),and the like. Further, an oxide, hydride, amide, or phenolate of analkali metal and/or an alkaline earth metal may be used as the catalyst.Examples thereof may include magnesium oxide (MgO), barium oxide (BaO),sodium aluminate (NaAlO₂), and the like. In addition, zinc oxide (ZnO),lead oxide (PbO), dibutyltin oxide ((C₄H₉)₂SnO), antimony trioxide(Sb₂O₃) may be used as the catalyst.

The catalyst in the melt polycondensation reaction may be used in anamount such that the metal equivalent of the catalyst is greater than 0mmole to 5 mmoles, greater than 0 mmole to 3 mmoles, or greater than 0mmole to 1 mmole, based on 1 mole of the entire diol compounds. If theamount of the catalyst is within the above range, it is possible toprevent the problems that the degree of polymerization falls below thetarget degree of polymerization and that a side reaction takes placewhereby such target physical properties as transparency are impaired.

In addition, in the process for preparing a highly heat-resistant,bio-based polycarbonate ester of the present invention, variousadditives may be added to the reactants, if necessary. For example, theadditives may include an antioxidant or a thermal stabilizer such ashindered phenol, hydroquinone, phosphite, and a substituted compoundthereof; a UV absorber such as resorcinol, salicylate, and the like; acolor protecting agent such as phosphite, hydrophosphite, and the like;and a lubricant such as montanic acid, stearyl alcohol, and the like. Inaddition, a dye and a pigment may be used as a colorant; carbon blackmay be used as a conductive agent, a colorant, or a nucleation agent;and a flame retardant, a plasticizer, an antistatic agent, and the likemay be used. The aforementioned additives may be used in an amount thatdoes not adversely affect the properties, especially transparency, ofthe final polymer.

Hereinafter, the present invention is described in more detail by thefollowing examples and comparative examples. However, these examples areprovided only for illustration purposes, and the present invention isnot limited thereto.

EXAMPLE Preparation Example 1: Preparation of DPT from TPA

A 1-L round-bottom flask equipped with a 4-blade agitator, inlets forphosgene and nitrogen gas, an outlet for discharged gases, and athermometer was charged with 100 g (0.60 mole) of TPA (SK Chemicals) and200 g of toluene. The mixture was stirred at room temperature. 1.28moles of phosgene gas was fed to the flask under atmospheric pressurefor 10 hours to carry out the reaction. Thereafter, nitrogen gas was fedto the flask for 2 hours to remove the residual phosgene andhydrochloric acid gas produced as a by-product, thereby yielding atransparent and homogeneous reaction solution. An analysis of thereaction solution by gas chromatography (GC) indicated that the ratio ofTPC was 49% by weight and that the reaction yield was 87%.

Then, 50% by weight of toluene initially supplied was distilled off fromthe reaction solution under a reduced pressure. Thereafter, a phenolsolution in which 121 g (1.28 moles) of phenol was dissolved in 121 g oftoluene was added through a dropping funnel to the reaction solution for2 hours. The mixture was stirred for 1 hour. Upon termination of thereaction, toluene was distilled off from the reaction solution under areduced pressure. The crude DPT thus obtained was purified byrecrystallization. Then, the purified DPT was dried at 90° C. undervacuum for 24 hours to obtain 162 g of DPT. Here, the reaction yield was85%, and the purity of DPT according to a GC analysis was 99.8%.

Preparation Example 2: Preparation of DPT from TPA

The procedures of Preparation Example 1 were repeated to prepare DPT,except that 1.27 g (0.017 mole) of dimethyl formamide was employed as anorganic catalyst. As a result of synthesis, the reaction yield was 84%,and the purity of DPT according to a GC analysis was 99.7%.

Preparation Example 3: Preparation of DPT from DMT

A 1-L round-bottom flask equipped with a 4-blade agitator, inlets forphosgene and nitrogen gas, an outlet for discharged gases, and athermometer was charged with 100 g (0.51 mole) of DMT (SK Chemicals),2.0 g (0.015 mole) of aluminum chloride, and 200 g of toluene. Themixture was stirred at room temperature. 1.10 moles of phosgene gas wasfed to the flask under atmospheric pressure for 10 hours to carry outthe reaction. Thereafter, nitrogen gas was fed to the flask for 2 hoursto remove the residual phosgene and hydrochloric acid gas produced as aby-product, thereby yielding a transparent and homogeneous reactionsolution. An analysis of the reaction solution by gas chromatography(GC) indicated that the ratio of TPC was 48% by weight and that thereaction yield was 89%.

Then, 50% by weight of toluene initially supplied was distilled off fromthe reaction solution under a reduced pressure. Thereafter, a phenolsolution in which 100 g (1.06 moles) of phenol was dissolved in 100 g oftoluene was added through a dropping funnel to the reaction solution for2 hours. The mixture was stirred for 1 hour. Upon termination of thereaction, toluene was distilled off from the reaction solution under areduced pressure. The crude DPT thus obtained was purified byrecrystallization. Then, the purified DPT was dried at 90° C. undervacuum for 24 hours to obtain 85 g of DPT. Here, the reaction yield ofDPT was 87%, and the purity of DPT according to a GC analysis was 99.7%.

Preparation Example 4: Preparation of DPT from TPA

A 1-L autoclave equipped with a 4-blade agitator, a cooling condenser,and a thermometer was charged with 100 g (0.6 mole) of TPA (SKChemicals), 565 g (6 moles) of phenol, and 1.83 g (0.01 mole) of zincacetate (Zn(OAc)₂) as a catalyst. Then, the mixture was heated to 100°C. and stirred, followed by pressurization to 1 kgf/cm² and temperatureelevation to carry out the reaction at 200° C. for 10 hours. In suchevent, water produced as a reaction by-product was discharged from theautoclave. Upon termination of the reaction, excessively added phenolwas distilled off under a reduced pressure to thereby finally obtain asolid product containing unreacted materials.

Then, 136 g of the solid product containing unreacted materials, 282 gof phenol, 400 g of toluene, and 0.92 g of zinc acetate were charged tothe autoclave as described above and then stirred at room temperature.Thereafter, the mixture was heated to 100° C. and subjected to thereaction at room temperature for 100 hours. In such event, waterproduced as a reaction by-product was discharged from the autoclave.Upon termination of the reaction, the reactants were cooled to 50° C.and separated by solid-liquid separation using a filter. Then, toluenewas removed from the separated toluene solution using an evaporator, andthe crude DPT thus obtained was purified by recrystallization.Thereafter, the purified DPT was dried at 90° C. under vacuum for 24hours to obtain 80 g of DPT. Here, the reaction yield was 42%.

Preparation Example 5: Preparation of DPT from DMT

A 1-L autoclave equipped with a 4-blade agitator, a cooling condenser,and a thermometer was charged with 100 g (0.51 mole) of DMT (SKChemicals), 480 g (5.10 moles) of phenol, and 1.72 g (0.01 mole) ofp-toluenesulfonic acid. Then, the mixture was heated to 100° C. andstirred, followed by pressurization to 1 kgf/cm² and temperatureelevation to carry out the reaction at 200° C. for 10 hours. In suchevent, methanol produced as a reaction by-product was discharged fromthe autoclave. Upon termination of the reaction, excessively addedphenol was distilled off under a reduced pressure to thereby finallyobtain a solid product containing unreacted materials.

Then, 140 g of the solid product containing unreacted materials, 240 gof phenol, 400 g of toluene, and 0.86 g of p-toluenesulfonic acid werecharged to the autoclave as described above and then stirred at roomtemperature. Thereafter, the mixture was heated to 100° C. and subjectedto the reaction at room temperature for 100 hours. In such event,methanol produced as a reaction by-product was discharged from theautoclave. Upon termination of the reaction, the reactants were cooledto room temperature and separated by solid-liquid separation using afilter. Then, toluene was removed from the separated toluene solutionusing an evaporator, and the crude DPT thus obtained was purified byrecrystallization. Thereafter, the purified DPT was dried at 90° C.under vacuum for 24 hours to obtain 106 g of DPT. Here, the reactionyield was 65%.

Example 1: Preparation of a Highly Heat-Resistance, Bio-BasedPolycarbonate Ester

An 18-L bench-scale reactor for polycondensation was charged with 1,995g (13.7 moles) of isosorbide (ISB; Roquette Freres), 444 g (1.37 moles)of DPT prepared in Preparation Example 1, 1.37 moles of DPCD (SKChemicals), 2,345 g (10.96 moles) of DPC (Changfeng), and 2 g of a 1%aqueous solution of sodium aluminate (NaAlO₂). The mixture was heated to150° C. Once the temperature reached 150° C., the pressure was reducedto 400 torr, and the temperature was then elevated to 190° C. over 1hour. During the temperature elevation, phenol was generated as aby-product of the polymerization reaction. When the temperature reached190° C., the pressure was reduced to 100 torr and maintained for 20minutes, and then the temperature was elevated to 230° C. over 20minutes. Once the temperature reached 230° C., the pressure was reducedto 10 torr, and then the temperature was elevated to 250° C. over 10minutes. The pressure was reduced to 1 torr or less at 250° C., and thereaction continued until the target stirring torque was reached. Uponarrival at the target stirring torque, the reaction was terminated. Thepolymerized product was pressurized and discharged as a strand, whichwas rapidly cooled in a water bath and then cut into pellets. Thepolycarbonate ester thus prepared had a glass transition temperature(Tg) of 168° C. and an intrinsic viscosity (IV) of 0.54 dL/g.

Examples 2 to 10: Preparation of a Highly Heat-Resistance, Bio-BasedPolycarbonate Ester

The same procedures as in Example 1 were repeated, except that the rawmaterials for polymers were as described in Table 1 below.

Comparative Example 1: Preparation of a Bio-Based Polycarbonate Esterfrom CHDM

The same procedures as in Example 1 were repeated to prepare apolycarbonate ester, except that 1,623 g (5.1 moles) of DPT prepared inPreparation Example 1, 2,549 g (11.9 moles) of DPC (Changfeng), 1,988 g(13.6 moles) of ISB (Roquette Freres), and 490 g (3.4 moles) of1,4-cyclohexanedimethanol (CHDM, SK Chemicals) were used while DPCD wasnot used. The polycarbonate ester thus prepared had a Tg of 155° C. andan IV of 0.55 dL/g.

Comparative Examples 2 and 3

The same procedures as in Comparative Example 1 were repeated to preparea polycarbonate ester, except that the raw materials for polymers wereas described in Table 1 below.

Test Example: Evaluation of Physical Properties

The polycarbonate esters of Examples 1 to 10 and Comparative Examples 1to 3 were each evaluated for their physical properties by the followingmethods. The measured physical properties are shown in Table 1 below.

Measurement of Glass Transition Temperature (Tg)

The glass transition temperature was measured using a differentialscanning calorimeter (Q20, TA Instruments) in accordance with ASTMD3418.

Measurement of Light Transmittance (T)

The light transmittance was measured for a specimen having a thicknessof 4 mm using a spectrophotometer (CM-3600A, Konica Minolta) inaccordance with ASTM D1003.

Measurement of Melt Flow Index (MI)

The melt flow index was measured using a melt indexer (G-01, TOYOSEIKI)under the conditions of 260° C. and a load of 2.16 kg in accordance withASTM D1238.

TABLE 1 Tg T MI ISB CHDM DPC DPCD DPT (° C.) (%) (g/10 min) Ex. 1 1 00.8 0.1 0.1 168 92 72 Ex. 2 1 0 0.7 0.2 0.1 164 92 100  Ex. 3 1 0 0.60.2 0.2 172 92 71 Ex. 4 1 0 0.5 0.2 0.3 180 91 41 Ex. 5 1 0 0.4 0.3 0.3178 92 70 Ex. 6 1 0 0.3 0.4 0.3 174 92 99 Ex. 7 1 0 0.2 0.4 0.4 182 9169 Ex. 8 1 0 0.1 0.4 0.5 190 91 39 Ex. 9 1 0 0.3 0.3 0.4 185 91 42 Ex.10 1 0 0.2 0.3 0.5 193 90 14 C. Ex. 1 0.8 0.2 0.7 0 0.3 155 90 35 C. Ex.2 0.8 0.2 0.6 0.1 0.3 152 91 65 C. Ex. 3 0.7 0.3 0.6 0 0.4 154 89 37

As shown in Table 1 above, the highly heat-resistant, bio-basedpolycarbonate esters prepared from diphenyl terephthalate (DPT)represented by Formula 5 in Examples 1 to 10 according to thepreparation process of the present invention had high glass transitiontemperatures as compared with the conventional bio-based polycarbonateester copolymerized from DPC and 1,4-diphenyl-cyclohexanedicarboxylate(DPCD) alone. Thus, the highly heat-resistant, bio-based polycarbonateesters are suitable for applications that require high heat resistance.

In addition, as the content of the repeat unit of DPCD increases(Examples 1, 2 and 4 to 6), the glass transition temperature is loweredas the content of the aliphatic ring monomer increases. But the meltflow index increases, resulting in an increased flowability.

Further, it was confirmed that as the content of the repeat unit of DPTincreases (Examples 2 to 4 and 6 to 8), the glass transition temperaturewas elevated whereas the melt flow index was decreased. In particular,in Example 3, the melt flow index is similar even though the glasstransition temperature is higher than that of Example 1. In Example 7,the melt flow index is similar even though the glass transitiontemperature is higher than those of Examples 1 and 3. In addition, inExample 10, the glass transition temperature had the highest value amongthe Examples, but the melt flow index was relatively low due to the lowcontent of the repeat unit of DPCD.

In addition, the light transmittance values in Examples 1 to 10 were all90% or more, which is equal to, or higher than, the maximum lighttransmittance of 90% of BPA-based polycarbonate products that have thesame level of heat resistance. In particular, the light transmittancevalues in Examples 1 to 9 were more excellent as 91% or higher.

Meanwhile, the bio-based polycarbonate esters prepared from1,4-cyclohexanedimethanol (CHDM) in Comparative Examples 1 to 3 had lowglass transition temperatures. Thus, they are not suitable forapplications that require high heat resistance. The melt flow indiceswere not high even though the glass transition temperatures wererelatively low as compared with the Examples. In particular, inComparative Example 3, the light transmittance was reduced as thecontent of the repeat unit of DPT was increased.

Accordingly, in the process of the present invention, it is possible tocontrol the properties of the bio-based polycarbonate ester attributableto the advantages and disadvantages of the carbonate bond and the esterbond by adjusting their ratios as well as the contents of the repeatunits of 1,4-diphenyl-cyclohexanedicarboxylate and diphenylterephthalate, depending on the target properties of high heatresistance thereof. The highly heat-resistant, bio-based polycarbonateester prepared by the process is excellent in heat resistance,transparency, and flowability. Thus, they can be advantageously used invarious applications that require high heat resistance.

The invention claimed is:
 1. An article molded from a bio-basedpolycarbonate ester having high heat resistance, wherein the highlyheat-resistant, bio-based polycarbonate ester comprises a repeat unit 1represented by the following Formula 1; a repeat unit 2 represented bythe following Formula 2; and a repeat unit 3 represented by thefollowing Formula 3, in molar fractions of x, y, and z, respectively:

 and wherein the highly heat-resistant, bio-based polycarbonate esterhas a glass transition temperature (Tg) of 160 to 240° C. and a meltflow index (MI) of 5 to 150 g/10 min when measured at 260° C. under aload of 2.16 kg, and wherein the molar fraction x for the repeat unit 1is a real number of greater than 0 to less than 1, the molar fraction yfor the repeat unit 2 is a real number of greater than 0 to 0.7, and themolar fraction z for the repeat unit 3 is a real number of greater than0 to 0.6.
 2. The article of claim 1, which is an automobile part.
 3. Thearticle of claim 1, which is an electric/electronic part.
 4. The articleof claim 1, which is a lighting part.
 5. The article of claim 1, whichis a medical product.
 6. The article of claim 1, which is a displaypart.
 7. The article of claim 1, which is an aviation part.
 8. Thearticle of claim 1, which is a machine part.
 9. The article of claim 1,which is a food container.
 10. The article of claim 1, wherein therepeat unit 1 is obtained from reaction of 1,4:3,6-dianhydrohexitol anda carbonate, the repeat unit 2 is obtained from reaction of1,4:3,6-dianhydrohexitol and 1,4-cyclohexanedicarboxylate, and therepeat unit 3 is obtained from reaction of 1,4:3,6-dianhydrohexitol anda terephthalate.
 11. An article molded from a bio-based polycarbonateester having high heat resistance, wherein the highly heat-resistant,bio-based polycarbonate ester comprises a repeat unit 1 represented bythe following Formula 1; a repeat unit 2 represented by the followingFormula 2; and a repeat unit 3 represented by the following Formula 3:

 and wherein the highly heat-resistance, bio-based polycarbonate esteris composed of the above repeat units 1 to 3, and when the molarfractions of the repeat units 1 to 3 are x, y, and z, respectively, x isa real number of greater than 0 to less than 1, y is a real number ofgreater than 0 to 0.7, z is a real number of greater than 0 to 0.6, andx+y+z is 1.